Ken Griffey Jr. of the Reds has asked (and received) permission from Major League Baseball to wear the No. 42, which has otherwise been retired from baseball in honor of Jackie Robinson, for one game on April 15, saying, "If he didn't achieve or didn't overcome the racial tension, would I be wearing this uniform?"
In the kind of sensible, respectful move of which there are far too few in MLB, the commissioner's office then suggested that other players also wear 42 on the 15th, which is the 60th anniversary of Robinson's major league debut. The Rockies' setup man LaTroy Hawkins has stepped up to the plate, so to speak, and will also wear 42 although, as he says, "I don't feel worthy, actually," and he's not just talking about his woeful pitching.
Mariano Rivera of the Yankees is, I believe, the last player still wearing 42 regularly, having been grandfathered in when the number was originally retired ten years ago. It would be nice if Derek Jeter insisted on wearing 42 on April 15, Rivera refused, they got into a fight and both landed on the 60-day disabled list, and the Yankees ended up in last place. After all, one of the things Jackie Robinson was emblematic of was beating the Yankees.